There is known an information processing device including a touch panel for outputting pressed position information corresponding to a pressed position, for performing processing based on the pressed position information outputted from the touch panel. For example, there is known a portable game machine including a liquid crystal display panel for displaying a game screen and a touch panel provided to be superimposed on the liquid crystal display panel, for specifying a position pressed by a player based on pressed position information inputted from the touch panel, and executing game processing corresponding to the position.
Incidentally, as the touch panel used for the information processing device described above, there is known one for outputting, when a plurality of positions are pressed, pressed position information indicating only one position, which has a predetermined relation with the plurality of positions, without outputting pressed position information indicating the plurality of positions. For example, there is known a touch panel of a resistive film type (a pressure sensitive type) for outputting, when a plurality of positions are pressed, pressed position information indicating the center of gravity of the plurality of positions. In an information processing device employing such a touch panel, it is difficult to specify a plurality of pressed positions based on only pressed position information outputted from the touch panel.
In this regard, in the touch panel of the resistive film type, when one position is newly pressed in the state in which another position is pressed, pressed position information indicating a midpoint of those positions is outputted. Thus, it is conceivable to calculate, based on coordinates of the position originally pressed and position coordinates (coordinates of the midpoint) outputted from the touch panel, coordinates of the position newly pressed (Patent Document 1). Similarly, when one position is newly pressed in the state in which a plurality of other positions are pressed, since pressed position information indicating the center of gravity of those positions is outputted, it is conceivable to calculate, based on coordinates of the plurality of positions originally pressed and position coordinates (coordinates of the center of gravity) outputted from the touch panel, coordinates of the position newly pressed.
[Patent Document 1] JP 2001-134382 A